Vibratory hammer having sequentially controllable sliding gripper

ABSTRACT

Disclosed is a vibratory hammer used to drive a pile in a foundation work of a construction site. A pair of main grip portions of a main gripper capable of gripping a pile are mounted on a pair of sliding arms capable of linear reciprocation. While the main grip portions and the sliding arms make linear reciprocation, a gap between the main grip portions is adjusted depending on a size and a shape of the pile (primary sliding operation). While a jaw pad of the main grip portion that substantially grips the pile also makes linear reciprocation by virtue of self-power of the main grip portion, the pile is gripped (secondary sliding operation). The primary and secondary sliding operations are sequentially performed.

CROSS REFERENCES TO RELATED APPLICATIONS

The present invention contains subject matter related to Korean PatentApplication No. 10-2014-0005173, filed in the Korean Patent Off ice onJan. 15, 2014, the entire contents of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This disclosure relates to a vibratory hammer, and more particularly, toa vibratory hammer used to drive e a pile in a foundation work of aconstruction site.

2. Description of Related Art

In general, in order to build many types of structures such as concretebuildings or bridges on the ground, it is necessary to perform afoundation work for burying a concrete pile, a steel pipe pile, anH-beam, or the like in order to allow the ground to support the weightof the structure.

Such a piling work is very important in construction of structures orbuildings. In particular, if the ground is soft, it is necessary toperform a foundation work for drilling and fixing a pile in a rock underthe ground surface.

In such a foundation work, a work of drilling a pile into the ground isreferred to as a pile driving work.

In a recent pile driving work, a vibratory hammer is employed. In thismethod, a vibrator is operated to vibrate a chuck in a drivingdirection, that is, in a direction perpendicular to the pile while apile is fixed. This vibration of the pile reduces a frictional forcebetween the pile and the ground to facilitate a driving work.

Such a vibratory hammer is installed in a boom of a construction machinesuch as an excavator and a shovel used in a civil engineeringconstruction, a building construction, and the like to perform a pilesocketing work.

In Korean Patent No. 10-0962081, US 2008-0310923A1, and the like, thereis disclosed a vibratory hammer, in which a main body includes aninternal vibrator for striking a pile and a pair of left and rightgrippers for gripping a pile and then socketing the pile into a pilehole.

In such vibratory hammers of the related art, a pile is gripped byactuating cylinders provided in both sides of each gripper while a pairof left and right grippers are fixed inside the main body. However, inthis case, since the width of the gripper widened by both cylinders islimited, it is difficult to grip a large-sized pile or beam.

In addition, in the vibratory hammers of the related art, a pair of leftand right grippers have a circular arc shape, and a pile is gripped bywidening or narrowing a gap between the grippers while one end isrotated with respect to a shaft as the cylinder is actuated. However, inthis case, since a direction where the cylinder pushes is different froma direction where the gripper grips the pile, the gripper fails toreceive a force in a direction where the cylinder rod is actuated, and aforce exerting direction changes depending on a pivot angle. Therefore,an eccentric force is applied, so that the gripper may be easilydistorted. This may generate a deformation or failure of the gripper andreduce a gripping force of the gripper.

SUMMARY OF THE INVENTION

In view of the aforementioned problems, a need exists for a vibratoryhammer capable of flexibly coping with various types of pile drivingworks for piles having various types and sizes, such as a sheet pile, asteel pipe pile, an H-beam, or an I-beam.

In addition, a need also exists for a vibratory hammer capable ofincreasing a gripping force of the gripper while reducing a deformationor failure of the gripper.

According to an aspect of this disclosure, there is provided asequentially controllable sliding gripper type vibratory hammercomprising: a main housing having a vibrator for striking a pile; a pairof sliding arms provided to face each other and linearly reciprocatableinside the main housing; an arm-actuating cylinder provided inside themain housing to move the pair of sliding arms; and a pair of left andright main grip portions mounted on the pair of sliding arms,respectively, the main grip portions moving along with the sliding armsto grip a pile by interposing a linearly and independentlyreciprocatable jaw pad.

In the vibratory hammer described above, each of the main grip portionsmay include a cylinder body, a rod that linearly moves to or out of thecylinder body, and a jaw pad that is provided in an end of the rod in acircular plate shape and has a plurality of wedged protrusions on a gripsurface for gripping the pile.

In the vibratory hammer described above, a pair of arm-actuatingcylinders may be provided for the pair of sliding arms, and each of thearm-actuating cylinders may push or pull each of the sliding arms inparallel.

The vibratory hammer described above may further comprise a pair of leftand right slide pins slidably connected to the pair of sliding arms toguide left-right linear reciprocation of the sliding arms, the pair ofslide pins being provided in each of the upper and lower plates.

In the vibratory hammer described above, each of the sliding arms mayinclude a front plate that is coupled to the main grip portion and has arod passage hole where a rod of the main grip portion is inserted in itscenter, a side plate arranged perpendicularly to the front plate, and aconnecting bracket extending from the side plate in an integral mannerand having upper and lower slide pin holes where the slide pins areinserted.

Meanwhile, the vibratory hammer described above may further comprise asubsidiary gripper configured to vertically drive a pile during a finishpile socketing, wherein the subsidiary gripper includes a fixed gripportion and a movable grip portion arranged to face each other in alower portion of the main housing to grip an upper end of the pile

The sequentially controllable sliding gripper type vibratory hammeraccording to an embodiment of this disclosure has the following effects.

First, since a sequential sliding gripper is employed, in which a pairof left and right main grip portions linearly reciprocates in thefront-back direction unlike a fixed type, and the jaw pad of each maingrip portion also reciprocates in the front-back direction, it ispossible to further widen a gap between the main grip portions forgripping a pile without increasing a size of the vibratory hammer.Accordingly, it is possible to grip a pile having a larger size andperform a pile driving work for various types and sizes.

Second, a pair of left and right main grip portions are implemented in asliding type unlike a pivot type. In addition, a movement direction(pile gripping direction) of the sliding arm connected to the main gripportion is in parallel with an actuating direction of the arm-actuatingcylinder for driving the main grip portion. Therefore, there is nopossibility of distortion in the main grip portion or the sliding arm.Therefore, it is possible to prevent a deformation or failure of thegripper and improve a gripping force of the gripper.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and additional features and characteristics of thisdisclosure will become more apparent from the following detaileddescription considered with reference to the accompanying drawings,wherein:

FIG. 1 is an exploded perspective view illustrating a vibratory hammeraccording to an embodiment of this disclosure;

FIG. 2 is a perspective view illustrating a vibratory hammer accordingto an embodiment of this disclosure;

FIG. 3 is a front view illustrating a vibratory hammer according to anembodiment of this disclosure;

FIG. 4 is a top plan view illustrating a vibratory hammer according toan embodiment of this disclosure;

FIG. 5 is a side view illustrating a vibratory hammer according to anembodiment of this disclosure;

FIG. 6 is a perspective view illustrating a main housing of thevibratory hammer according to an embodiment of this disclosure;

FIG. 7 is an exploded perspective view illustrating a main housing ofthe vibratory hammer according to an embodiment of this disclosure;

FIG. 8 is an exploded perspective view illustrating a subsidiary gripperof the vibratory hammer according to an embodiment of this disclosure;and

FIGS. 9A to 9C are operational state diagrams illustrating anoperational state of the vibratory hammer according to an embodiment ofthis disclosure.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, Hereinafter, an embodiment of this disclosure will bedescribed in detail with reference to the accompanying drawings.

FIG. 1 is an exploded perspective view illustrating a vibratory hammeraccording to an embodiment of this disclosure. FIGS. 2 to 5 are aperspective view, a front view, a top plan view, and aside view,respectively, illustrating the vibratory hammer according to anembodiment of this disclosure.

Referring to FIGS. 1 to 5, the vibratory hammer includes a mount cap300, a housing bracket 200, a main housing 100, and a mount plate 104.

The mount cap 300 is connected to a boom bracket, a quick coupler, orthe like provided in a leading end of a boom of a construction machinesuch as an excavator and a shovel.

The housing bracket 200 is interposed between the mount cap 300 and themain housing 100 to couple the main housing 100 to the mount cap 300 andserves as a cover for protecting an exterior of the main housing 100. Itis noted that a concave portion 201 hollowed inward from the frontsurface is formed in the upper plate of the housing bracket 200 toprevent an interference to a pile when the main gripper installed in themain housing 100 grips the pile.

The main housing 100 provides a space for housing the main gripperhaving a pair of main grip portions 130 used to grip a pile, anactuating cylinder 120 as an actuator for actuating the main gripper,and a vibrator 150 that provides vibration for socketing a pile into apiling hole of the ground.

The mount plate 104 is configured to finish the bottom of the mainhousing 100 in a rectangular plate shape and is provided with asubsidiary gripper 140 capable of gripping an upper end of the pile.

In the vibratory hammer according to an embodiment of this disclosureconfigured as described above, the main gripper grips the pile in asequential sliding manner. Specifically, a pair of the main gripportions 130 are not fixedly installed in the main housing, but areinstalled in a linearly reciprocatable manner along a front-backdirection (primary sliding). In addition, each of the main grip portions130 also includes an actuator such as a motor or a cylinder, capable ofdriving a jaw pad that directly grips the pile by virtue of self-power(secondary sliding).

In this regard, FIGS. 6 and 7 are a perspective view and an explodedperspective view, respectively, illustrating the main housing of thevibratory hammer embedded with the main gripper described above.

Referring to FIGS. 2 to 7, the main housing 100 is internally providedwith a pair of left and right assemblies arranged symmetrically. Eachassembly includes a main grip portion 130 configured to grip a pile, asliding arm 110 that is connected to the main grip portion 130 andreciprocates in the front-back direction, an arm-actuating cylinder 120that provides a driving force for actuating the sliding arm 110, and avibrator 150 that applies vibration for striking the pile.

The main housing 100 has a rectangular frame shape having an openedfront surface. More specifically, the main housing 100 includes a pairof side plates 101 vertically erected in both sides to face each other,a rear plate (not illustrated) vertically erected in the back side andconnected between the pair of side plates 101, and upper and lowerplates 102 and 103 extending horizontally across the interior of themain housing 100 to face each other below an upper end of the pair ofside plates 101 and above a lower end of the pair of side plates 101,respectively.

A pair of sliding arms 110 serving as a member for moving the main gripportion 130 are symmetrically provided to face each other in a spaceformed between the upper and lower plates 102 and 103 of the mainhousing 100. The pair of sliding arms 110 linearly reciprocates in theleft-right direction by actuating the arm-actuating cylinder 120.

Now, the sliding arm 110 will be described more specifically withreference to FIG. 7. The sliding arm 110 generally includes a frontplate 111, a side plate 112, and a connecting bracket 113.

A rod passage hole 111 a where a rod 132 of the main grip portion 130 isinserted is formed in the center of the front plate 111. A plurality offastening holes are formed around the rod passage hole 111 a. Bolts areinserted into the fastening holes and are fastened to connect thecylinder body 131 of the main grip portion 130 to the front plate 111.In an integral manner, the side plate 112 extends perpendicularly to thefront plate 11 in the end of the front plate 111, and the connectingbracket 113 vertically extends on a surface opposite to a surface wherethe main grip portion 130 is provided.

Meanwhile, a member for guiding the linear front-back reciprocation ofthe sliding arm 110 is provided in the main housing 100.

For this purpose, a pair of the slide pins 105 extending horizontallyside by side are provided in the upper and lower plates 102 and 103 ofthe main housing 100 for each of the left and right assemblies (a totalof four slide pins 105 are provided). One end of each slide pin 105 isfixed to the side plate 101 of the main housing 100 in a penetratingmanner, and the other end is fixed to a slide pin bracket 108protrudingly provided in the upper or lower plate 102 or 103 in apenetrating manner.

Each sliding arm 110 linearly reciprocates in the front-back directionalong the slide pin 105 while it is slidably engaged with a pair ofupper and lower slide pins 105 provided over and under the sliding arm110, respectively.

For this purpose, a slide pin hole 113 a where the slide pin 105 isinserted is formed in each of the upper and lower portions of theconnecting bracket 113 of the sliding arm 110.

A single arm-actuating cylinder 120 serving as a member for linearlyreciprocating the sliding arm 110 in the front-back direction isprovided for each of the pair of sliding arms 110. A pair of slidingarms 110 are arranged oppositely in the left and right sides of theupper and lower plates 102 and 103 of the main housing 100.

For example, one of the arm-actuating cylinders 120 is arranged in theright side of the upper plate 102 to actuate the right sliding arm 110of the main housing 100, and the other arm-actuating cylinder 120 isarranged in the left side of the lower plate 103 to actuate the leftsliding arm 110 of the main housing 100.

A pair of arm-actuating cylinders 120 are arranged to face each other inthe opposite direction. Specifically, the arm-actuating cylinders 120are arranged such that the rear surfaces of the cylinder bodies turnback to each other while each cylinder rod is directed to the side plate101 of the main housing 100.

The rod of the arm-actuating cylinder 120 is connected to the slidingarm 110 while the arm-actuating cylinder 120 is provided in parallelwith the upper and lower plates 102 and 103. As a result, the slidingarm 110 can linearly reciprocate in the front-back direction in parallelwith the actuating direction of the rod of the arm-actuating cylinder120.

A rear end of the cylinder body of the arm-actuating cylinder 120 isfixed to a cylinder bracket 108 protrudingly provided at a certainheight from the upper or lower plate 102 or 103 using a pin. A front endof the rod of the arm-actuating cylinder 120 is also connected to thesliding arm 110 using a pin.

A structure for fixing the arm-actuating cylinder 120 to the upper orlower plate 102 or 103 will be described in more detail. A cylinder pinhole 122 where the cylinder pin 106 is inserted is perforated in therear end of the cylinder body of the arm-actuating cylinder 120 in thefront-back direction. In addition, the cylinder bracket 108 has a pairof plates facing each other with a certain interval, and each plate hasa cylinder pin hole 108 a perforated in the front-back direction, wherethe cylinder pin 106 is inserted. As a result, the arm-actuatingcylinders 120 are fixed to the upper and lower plates 102 and 103 of themain housing 100 by horizontally inserting the cylinder pin 106 intoeach of the cylinder pin holes 122 and 108 a while a part of thearm-actuating cylinder 120 where the cylinder pin hole 122 is formed isinterposed between the cylinder bracket 108.

A structure of coupling the arm-actuating cylinder 120 and the slidingarm 110 will be described in more detail. A rod pin hole 121 where therod pin 107 is inserted is perforated in a front end of the rod of thearm-actuating cylinder 120 along a vertical direction. In addition, arod pin hole 113 b perforated along a vertical direction in an extendingportion horizontally extending from a portion where the slide pin hole113 a is formed in the upper or lower portion of the connecting bracket113 of the sliding arm 110. As a result, while the rod pin hole 121 ofthe arm-actuating cylinder 120 and the rod pin hole 113 b of theconnecting bracket 113 of the sliding arm 110 are disposedconcentrically along a vertical direction, the rod pin 107 is verticallyinserted into each rod pin hole 121 and 113 b, so that the arm-actuatingcylinder 120 and the sliding arm 100 are connected to each other.

A pair of main grip portions 130 of the main gripper are configured togrip a pile and guide the pile in an initial pile socketing. Each maingrip portion 130 is mounted on the sliding arm and linearly reciprocatesin the left-right direction along with the sliding arm.

As a result, a pair of left and right main grip portions 130 move a pilesuch as a sheet pile, a steel pipe pile, an H-beam, or an I-beam havingdifferent sizes to be close to or apart from each other inside the mainhousing in order to adjust a gap therebetween.

Meanwhile, the main grip portion 130 includes an actuator member such asa motor or a cylinder. Therefore, as recognized from FIGS. 9A to 9C, thepile can be gripped by advancing the jaw pad 133 disposed in the frontsurface by actuating the actuator.

According to an embodiment of this disclosure, a cylinder is employed asan actuator member.

This will be described in more detail with reference to FIG. 6. The maingrip portion 130 includes a cylinder body 131 where a hydraulic pressureis internally applied, a rod 132 that slides into or out of the cylinderbody 131 to make a linear reciprocation, and a jaw pad 133 coupled to anend of the rod 132. A pair of main grip portions 130 are horizontallymounted on the sliding arm 110 such that the jaw pads 133 face eachother.

The jaw pad 133 having a circular plate shape is coupled to a leadingedge of the rod 132 by fastening a bolt or the like, and a surface forgripping a pile has a plurality of wedged protrusions. As a result, itis possible to stably grip a pile without a problem such as slippingwhen the pile is gripped.

As described above, the main grip portion 130 is fixedly coupled to thefront plate 111 of the sliding arm 110. Specifically, while the rod ofthe main grip portion 133 is inserted into the rod passage hole 111 aformed in the center of the front plate 111 of the sliding arm 110, afront surface of the cylinder body 131 is fixedly coupled to the frontplate 111 of the sliding arm 110 by fastening bolts through a pluralityof fastening holes formed along the periphery of the rod passage hole111 a.

As a result, a gap for gripping the pile is adjusted as the main gripportions 130 make a linear movement along with the sliding arms 110 suchthat the gap can be widened or narrowed (primary sliding). In addition,as the rod 132 attached to the jaw pad 133 makes a linear reciprocationdepending on the hydraulic pressure of the cylinder body 131, the pileis gripped or released (secondary sliding).

Meanwhile, the vibrator 150 is provided in a rear plate of the mainhousing 100. Therefore, vibration is generated using a pair of eccentricweights 153 and a pair of driving gears 152 operated by the motor 151.

For this purpose, a rotational shaft 154 is provided to extend acrossthe eccentric weight 153, and a motor 151 for driving the rotationalshaft 154 is provided in one of the pair of eccentric weights 153. Inaddition, a pair of driving gears 152 meshing with each other arecoupled to the corresponding rotational shafts 154.

Therefore, as the motor 151 is operated, both the driving gears 152meshing with each other are driven by virtue of rotation of therotational shaft 154. Finally, vibration is generated by virtue of aneccentric rotational force exerted by a pair of eccentric weights 153.This vibration is used to strike the pile.

In addition, a subsidiary gripper 140 capable of vertically driving thepile during the finish pile socketing is provided under the main housing100.

FIG. 8 is an exploded perspective view illustrating the subsidiarygripper of the vibratory hammer according to an embodiment of thisdisclosure.

The subsidiary gripper 140 is installed on the bottom surface of themount plate connected to the lower ends of both side plates 101 of themain housing 100.

The subsidiary gripper 140 includes a fixed grip portion 141 and amovable grip portion 142 arranged to face each other and capable ofgripping an upper end of the pile. In this case, jaw pads 141 b and 142b for stably gripping a pile are installed in the front surfaces of thefixed grip portion 141 and the movable grip portion 142, respectively.

The fixed grip portion 141 includes a fixed block 141 a that is fixed tothe mount plate 104 and has a rectangular parallel-piped shape and afront plate 141 b coupled to the front surface of the fixed block 141 aby fastening a bolt or the like.

Similar to the main grip portion 130, the movable grip portion 142 has acylinder type actuator. The jaw pad 142 b provided in the front surfaceof the rod 142 c moving in the front-back direction by virtue ofhydraulic actuation of the cylinder body 142 a advances toward the jawpad 141 b of the fixed grip portion 141 b in the opposite side so as togrip a pile together.

Between the movable grip portion 142 and the fixed grip portion 142, afixed plate 143 where the movable grip portion 142 is fixed is fixedlyprovided perpendicularly on the mount plate 104. A rod passage hole 143a where the rod 142 c of the movable grip portion 142 is inserted isformed in the center of the fixed plate 142, and a plurality offastening holes are formed around the rod passage hole 143 a.

As a result, the front surface of the cylinder body 142 a can beconnected to the fixed plate 143 horizontally by fastening bolts whilethe rod 142 c of the movable grip portion 142 is inserted into the rodpassage hole 143 a of the fixed plate 143.

Therefore, in the pile socketing, the pile approaches the ground surfacewithin a certain distance, and then, the pile may be socketed byswitching to the subsidiary gripper 140 in the finish pile socketing.Finally, a driving force applied from the vibrator 150 can be moreeffectively transmitted to the pile. Therefore, it is possible to applya driving force in a vertical direction in parallel with the pile anduse the driving force at maximum without a loss. Accordingly, it ispossible to improve workability in the pile socketing.

Meanwhile, each front surface of the upper plate, the side plates, andthe mount plate 104 of the main housing is positioned in the backside ofthe main gripper in order to prevent an interference to the pile whenthe pile is gripped by the main gripper installed in the main housing100.

In addition, a plurality of cushion rubbers 160 are interposed betweenthe main housing 100 and the housing brackets 200 to absorb vibration ofthe vibrator 150.

Now, a process of socketing a pile using the vibratory hammer configuredin this way will be described.

FIGS. 9A to 9C are operational state diagrams illustrating anoperational state of the vibratory hammer according to an embodiment ofthis disclosure.

An operator who drives a construction machine may perform overalloperations described in the following description.

FIG. 9A is a diagram illustrating a state that a gap between the pair ofmain grip portions 130 of the vibratory hammer is widened at maximum.

In this state, it is possible to grip a pile by adjusting the gapbetween the main grip portions 130 depending on a type or a size of thepile, such as a sheet pile, a steel pipe pile, an H-beam, or an I-beam,to be socketed to the ground surface.

As illustrated in FIGS. 9A to 9C, as the arm-actuating cylinder 120 isactuated, the gap between the main grip portions 130 is narrowed tomatch a size of a pile to be gripped while the sliding arm linearlymoves along the sliding pin 105. In this case, the gap between the maingrip portions 130 is not adjusted to exactly match the pile size.Instead, the gap is adjusted to be larger than the pile size.Accordingly, the pile can easily enter the gap between the main gripportions 130.

In this state, the jaw pads 133 of the main grip portions 130 advance toeach other to tightly grip the pile.

As illustrated in FIGS. 9A to 9C, as a hydraulic pressure is applied tothe cylinder body 131 of the main grip portion 130 while the pile H isinterposed between the pair of main grip portions 130, the rods 132 ofthe main grip portions 130 move to the pile H side, and the jaw pads 133press the side surface of the pile in order to tightly grip the pile.

In this state, the pile approaches the ground surface, and the vibrator10 is operated. Then, it is possible to socket the pile using thevibration.

When the pile is nearly completely socketed, the main grip portions 130that grip the pile in the side surface recede from each other toseparate the pile. Subsequently, the subsidiary gripper 140 grips theupper end of the pile. Then, in this state, a finish socketing isperformed by vertically driving the pile. As a result, a socketing for apile is completed.

In this manner, according to an embodiment of this disclosure, it ispossible to move a pair of main grip portions to adjust a gaptherebetween inside the main housing and grip a pile by actuating thejaw pads of the main grip portions to move toward each other usingself-power. Therefore, it is possible to grip various sizes and shapesof piles

Although exemplary embodiments of the present invention have been shownand described, it will be apparent to those having ordinary skill in theart that a number of changes, modifications, or alterations to theinvention as described herein may be made, none of which depart from thespirit of the present invention. All such changes, modifications andalterations should therefore be seen as within the scope of the presentinvention.

What is claimed is:
 1. A sequentially controllable sliding gripper typevibratory hammer comprising: a main housing having a vibrator forstriking a pile; a pair of sliding arms provided to face each other andlinearly reciprocatable inside the main housing; an arm-actuatingcylinder provided inside the main housing to move the pair of slidingarms; and a pair of left and right main grip portions mounted on thepair of sliding arms, respectively, the main grip portions moving alongwith the sliding arms to grip a pile by interposing a linearly andindependently reciprocatable jaw pad.
 2. The sequentially controllablesliding gripper type vibratory hammer according to claim 1, wherein eachof the main grip portions includes a cylinder body, a rod that linearlyslides in or out of the cylinder body, and a jaw pad that is provided inan end of the rod in a circular plate shape and has a plurality ofwedged protrusions on a grip surface for gripping the pile.
 3. Thesequentially controllable sliding gripper type vibratory hammeraccording to claim 2, wherein a pair of arm-actuating cylinders areprovided for the pair of sliding arms, and each of the arm-actuatingcylinders pushes or pulls each of the sliding arms in parallel.
 4. Thesequentially controllable sliding gripper type vibratory hammeraccording to claim 3, wherein an upper plate and a lower plate areprovided over and under the main grip portion, respectively, across aninterior of the main housing, and the pair of arm-actuating cylindersare arranged oppositely in the left and right sides of the upper andlower plates.
 5. The sequentially controllable sliding gripper typevibratory hammer according to claim 4, further comprising a pair of leftand right slide pins slidably connected to the pair of sliding arms toguide left-right linear reciprocation of the sliding arms, the pair ofslide pins being provided in each of the upper and lower plates.
 6. Thesequentially controllable sliding gripper type vibratory hammeraccording to claim 5, wherein each of the sliding arms includes a frontplate coupled to the main grip portion, a side plate arrangedperpendicularly to the front plate, and a connecting bracket extendingfrom the side plate in an integral manner and having upper and lowerslide pinholes where the slide pins are inserted.
 7. The sequentiallycontrollable sliding gripper type vibratory hammer according to claim 6,wherein a rod passage hole where a rod of the main grip portion isinserted is formed in a center of the front plate of each of the pair ofsliding arms.
 8. The sequentially controllable sliding gripper typevibratory hammer according to claim 6, wherein a first rod pin holewhere a rod pin is inserted is formed in an end of a rod of thearm-actuating cylinder, and the connecting bracket of the sliding armhas a second rod pin hole where the rod pin inserted into the first rodpin hole is inserted.
 9. The sequentially controllable sliding grippertype vibratory hammer according to claim 1, further comprising asubsidiary gripper configured to vertically drive a pile in a finishpile socketing, wherein the subsidiary gripper includes a fixed gripportion and a movable grip portion arranged to face each other in alower portion of the main housing to grip an upper end of the pile.